This invention relates generally to structural frames and other articulated supporting structures. More specifically to three-dimensional structural trusses, i.e., supporting structures whose primary load-bearing capacity is attributable to extension of the structure in three dimensions.
A structural truss may generally be considered to be an open, skeletal assembly of struts joined at nodes to achieve a supporting structure of high load-bearing capacity relative to its weight, i.e., high specific-structural strength. Trusses are usually based on the geometric triangle to take advantage of its inherent rigidity in supporting a coplanar load.
The struts of a truss are commonly straight and joined together at nodes by means of various types of male and female coupling devices. Thus, the struts are discontinuous. But some of the highest specific-strength materials consist of strong filaments embedded in less strong matrices, and such materials are difficult to join to coupling devices without introducing substantial extra weight. Thus, it is desirable to use continuous strut-like members that do not need nodal coupling devices in forming light-weight structures.
The present invention provides a truss that uses specially designed, articulated, ring-like members for its struts. It is fundamentally periodic in three dimensions. Its geometric form causes it to have three-dimensional stability without depending on lateral stabilizing members or complex networking. As a result of its periodicity, the truss may be built up in a regular fashion by "repeating" a fundamental unit in the three dimensions to the extent desired. Further, this truss design continues to take advantage of the inherent rigidity of the skeletal triangle. Still further, the truss design achieves these advantages with maximum geometric efficiency, i.e., the minimum number of struts per node (four) that is required for stability of an articulated, periodic, 3D structure. This provides a maximum of open space in the structure; thereby improving its usefulness.